Field of the Invention
The present invention relates to an optical apparatus and particularly to an optical apparatus provided with a calibration function to correct a light pattern formed on a sample.
Description of the Related Art
Conventionally, microscopes have been known that perform patterned irradiation with light by using a spatial light modulator (SLM).
The spatial light modulators used for patterned irradiation are roughly classified into: phase-modulation spatial light modulators located at a position optically conjugate to the pupil position of an objective; and intensity-modulation spatial light modulators located at a position optically conjugate to the focal position of an objective.
For example, LCOS (liquid crystal on silicon) is known as a phase-modulation spatial light modulator. Japanese Laid-open Patent Publication No. 2011-099986 discloses a microscope that includes: means for performing patterned irradiation with stimulation light by using a phase-modulation spatial light modulator composed of LCOS; and means for causing scan means to scan a sample with light so as to obtain the image of the sample.
Meanwhile, a DMD® (Digital Micromirror Device) is known as an intensity-modulation spatial light modulator.
In general, to perform patterned irradiation with light using a microscope, a pattern shape to be formed on a sample or a position to be irradiated is designated on a screen displaying the image of the sample. In fact, however, patterned irradiation often fails to follow, for example, the position or the shape designated on the screen due to an error caused by the optical system. Thus, a technology is demanded for calibrating microscopes and optical systems provided with a microscope so as to perform patterned irradiation in accordance with designation on a screen.